The most fundamental classification of individuals into social groups is whether an individual belongs to your group (ingroup member) or to some other group (outgroup member). Individuals tend to favor their own group as compared to the outgroup; perceive outgroup members as being different from ingroup members and homogeneous in their own attitudes and behavior; and perceive ingroup members as similar to one another, but possessing a variety of opinions and behaviors. Memory for ingroup and outgroup members' behaviors is influenced by expectancies generated by social categorization. This study examined the effect of social categorization on memory for attitudes of ingroup and outgroup members. College students (N=39) were assigned to a group affiliation based on an arbitrary criterion and were informed that the other person in the study was in their group, the other group, or given no group affiliation for the person. Subjects were given an attitude profile of the person constructed to contain an equal number of similar and dissimilar attitudes to their own. The results of a free recall task indicated that subjects recalled both similarities and differences about ingroup members, but remembered only differences about outgroup members. These findings suggest that social categorization affects the encoding of information which leads to a differential recall effect. (Author/NB)